Captain George Ford said he was proud of his young England colleagues after they completed a clean sweep of victories on their summer tour.
A much-changed England side shrugged off two lengthy delays caused by lightning to beat the United States 40-5 in Washington DC on the back of a 2-0 series win in Argentina.
Curtis Langdon, Luke Northmore, Cadan Murley, Jack van Poortvliet, Harry Randall and Gabriel Oghre, one of six debutants, grabbed England’s six tries with Ford landing four conversions with one from another new face, Charlie Atkinson.
“The boys have been unbelievable all tour. They deserve that tonight,” said Ford, who won his 102nd cap. “It is a proud moment for the families, so we will celebrate.
“There has been a lot of hard work and the conditions were difficult tonight.
“We have won all three games, we have had six new caps, I am proud of the effort of everyone.”
After kick-off at Audi Field was delayed due to an electrical storm in the American capital, England seized control when the Eagles were reduced to 14 by a deliberate knock-on from outside-half Chris Hilsenbeck.
Langdon was the beneficiary of a driving line-out for the first score and then new boy Max Ojomoh slipped in fellow centre Northmore for a simple score under the posts.
Alex Dombrandt and debutant Jack Carpenter had scores ruled out on either side of a 40-minute delay for lightning before Murley raced over in the final play of the first half.
Van Poortvliet, showing his sound positional sense, went over straight after the restart and England were camped in the Americans’ 22 for most of the second period.
The hosts held out until Immanuel Feyi-Waboso sliced through to send the supporting Randall over and Bristol hooker Oghre burst out of a maul to score as England turned to the bench.
The US were finally on the scoreboard in the final seconds as a well-worked ploy at the front of a line-out saw Chris Poidevin put Shilo Klein over for a consolation score.
“It is a big challenge, but the boys stayed on it,” said home captain Benjamin Bonasso. “We trusted the process and got a try at the end of the game.
“We have got to keep going. Facing this type of speed and conditions always makes you better.”